The mostly white men who gathered to defend the statue of Confederate Gen. Robert E. Lee, and white nationalism in general, came from many walks of life. And as they, one by one, began to be identified and their images circulated in the news media, their family members expressed everything from denial to disavowal about their loved one’s beliefs and actions.

The mother of James Alex Fields Jr., the 20-year-old accused of driving a car into a group of people in Charlottesville, Virginia, on Saturday, killing a young woman and injuring 19 people, says she had no idea that her son was attending a white nationalist demonstration. Conversely, the father of Peter Tefft, who was spotted marching with white supremacists in Charlottesville, released a statement expressing regret that he had kept silent for too long about his son’s slide into extremism.

People who study white supremacist recruitment say there is no single path toward extreme groups like the neo-Nazis. They say the people closest to these extremists may either have no idea what’s going on or don’t know how to confront them. But there are some commonalities among those who join these movements.

Knowing the warning signs of radicalization could help concerned family members and friends intervene before a teen or young adult slides into extremism, experts say. And it could also help prevent the next terrorist attack.

Who is most likely to join?

People who join violent extremist groups tend to score low on measures of what researchers call “integrative complexity,” a scale of one’s ability to think about things in a nuanced, multifaceted way, explained Alejandro Beutel, who researches violent extremist ideologies.

“People who are the most extreme and the most violent score low on these types of things,” Beutel said. “They often tend to think in very black-and-white ways rather than in much more complex, gray ways.“

This kind of thinking process makes it easier to accept the simplistic ideologies that many of these groups espouse, like the notion that whites make up an “Aryan race” that should be privileged above other racial groups or that there is a worldwide Jewish conspiracy to destroy the white race.

Childhood trauma is another thing that many members of extremist groups have in common. Researchers at the University of Nebraska at Omaha examined the life histories of 44 white supremacists across the U.S. and found that 45 percent said they experienced physical abuse, 21 percent experienced sexual abuse and 46 percent said they were neglected as children — rates that are all higher than the national average but are roughly on par with reported rates of childhood abuse and neglect among people who are incarcerated.

The same study also found that 62 percent had either tried to kill themselves or had seriously considered it, and 57 percent said they had mental health problems either before joining the extremist group or during their time with the group. Seventy-two percent had substance use disorders, and 54 percent had dropped out or been expelled from school.

Any successful program that helps people leave violent extremist groups would need to be able to address these non-ideological issues in addition to deprogramming the hateful ideology, Beutel said.

Why do they join?

While the term “white supremacy” indicates that people in the movement feel superior to other races, Beutel’s own research shows that fear of losing one’s place in society rather than a feeling of dominance is what draws people to these movements.

For instance, an analysis of white supremacist Twitter messages by researcher J.M. Berger, co-author of ISIS: The State of Terror, shows that groups mostly focus on the theme of “white genocide” — the notion that other races and ethnic groups are overtaking whites in the U.S. — for recruitment.

The notion that the white race is diminishing is the most effective gateway argument to the movement because it’s grounded in a fact: The U.S. is set to become a minority-majority country between 2044 and 2055.

”Whites, for the first time in our country, will no longer hold an absolute demographic majority,” Beutel said. “With that are going to come socioeconomic, political and cultural changes of the very definition about what it means to be an American, and there are many people who are uncomfortable with that.“

The white supremacist narrative may find fertile soil in the mind that has been exposed to racially coded language that dehumanizes minority groups, Beutel continued. If, for instance, they’ve been exposed to decades of right-wing media calling black victims of police violence “thugs” and “beasts,” or if their family members rant frequently about “global elites” who control the world’s money, the white genocide narrative is especially appealing because it offers a simplistic answer to complex policy questions.

Other facets of supremacist ideology, like pseudoscientific claims about white genetic superiority or quasireligious notions that white people are God’s chosen ones, may come later as recruits go deeper into the movement, Beutel said, but they’re not effective opening arguments for new members because they require bigger leaps of logic.

And similar to street gangs and other fringe groups, white supremacist organizations can offer people a sense of purpose and camaraderie because they unite people around shared ideals.

How can you intervene?

Parents and caregivers need to understand that interest in white supremacy groups is a serious issue that can have lifelong consequences for their children, said Peter Weinberger, a research scientist at the University of Maryland’s National Consortium for the Study of Terrorism and Responses to Terrorism. Parental figures should approach the issue with the same urgency and gravity as those who confront their children about illegal drug use or other criminal acts.

“This isn’t just a phase or acting out,” Weinberger said. “This is extremism and, in many instances, domestic terrorism or criminality.”

If parents and friends aren’t empowered to intervene, the situation could create a bystander effect, which is when people assume someone else will do something to address the issue. Then the problem gets out of hand, said Weinberger.

Indeed, in an open letter, Pearce Tefft, father of Peter Tefft, wrote that he regretted standing by while he watched his son become more involved in the white nationalist movement.

”We have been silent up until now, but now we see that this was a mistake,” Tefft wrote. “It was the silence of good people that allowed the Nazis to flourish the first time around, and it is the silence of good people that is allowing them to flourish now.”

Interventions should also be community-based, Weinberger said, in order for people to not feel singled out when asking for help. Faith communities, schools and mentoring organizations should speak to parents about the signs of online radicalization and the importance of intervening immediately.

It’s important to note that just because someone socializes with extremists or watches ideological propaganda, that doesn’t mean they will go on to commit terrorism. Researchers are still figuring out what makes some ideological extremists turn violent. But more effective than trying to predict violence is attempting to prevent radicalization in the first place, says Beutel.

If parents know that their child is hanging out with extremists or watching videos of neo-Nazi violence, they should take those actions as a cry for help and seek therapy with someone who has experience with extremism.

“You can’t predict whether those individuals are going to actually engage in that violence,” he said. “But does that mean that a friend or parent or some other family member shouldn’t be concerned that maybe they should get that person counseling or some other forms of assistance? Of course not.”

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